Writing pen

ABSTRACT

A multicolor writing pen having a plurality of refill holders, selecting means for moving the refill holders and a switching element having a rotatable cylinder. The peripheral surface of the cylinder is provided with a plurality of cam tracks; and each cam track engaging a follower associated with a refill holder so that when a selected refill holder is moved into its operative position, the switching element rotates so that it holds the selected refill in its writing position.

lnventor Gerold Anderka Hamburg, Germany Appl. No. 884,630 Filed Dec. I2, 1969 Patented June 22, I971 Assignee Riepe-Werk Hamburg, Germany Priority Dec. 17, 1968 Germany WRITING PEN 9 Claims, 10 Drawing Figs.

References Cited UNITED STATES PATENTS 3,025,833 3/1962 Fend 3,174,462 3/1965 Bross... 3,225,747 12/1965 Schmidt Primary ExaminerLawrence Charles Att0rneyLilling & Siegel ABSTRACT: A multicolor writing p'en having a plurality of refill holders, selecting means for moving the refill holders and a switching element having a rotatable cylinder. The peripheral surface of the cylinder is provided with a plurality of cam tracks; and each cam track engaging a follower associated with a refill holder so that when a selected refill US. Cl 401/33 holder is moved into its operative position, the switching elelnt.Cl 843k 27/12 ment rotates so that it holds the selected refill in its writing Field of Search 401/ 3 l -33 position.

a l E 2 7 r l 45 -46 3?; v I 7 49 WRITING PEN BRIEF INTRODUCTION TO THE INVENTION This invention relates to multicolor writing pens.

Multicolor writing pens in which a desired refill holder can be advanced into writing position according to the selected position occupied under the effect of gravity by a suspended rod have heretofore been proposed. In such pens, the pushbutton selector mechanism consists of a single cam slot and slider mechanism, in which the slider is a projection or ball, and which is located directly below the pushbutton and above the rod. This arrangement necessitates a relatively long working stroke. Moreover, the single cam slot is also subject to considerable wear. In other multicolor writing pens, particularly of the kind containing slides projecting from the barrel and movable in longitudinal slots for displacing the several writing refills, the retaining mechanism is a rotatable sleeve provided with cam slots engaged by the several slides for rotating the sleeve and for thus keeping the refill holders in operative position or causing them to be retracted. It has also been proposed to provide a cam slot in each of the refill holders and to use a specially mounted switching spider for generating rotation and hence causing the retention or retraction of the refill holders. The sleeve as well as the switching spider must be of relatively large diameter or complex components which are unsuitable for mass production purposes.

BRIEF SUMMARY OF THE INVENTION According to the present invention, there is provided a multicolor writing pen comprising, a plurality of refill holders each of which can be moved into an operative or writing position against the action of a biasing spring, means for selecting which refill holder is to be so moved, and a switching element comprising a rotatable cylinder the peripheral surface of which is provided with a plurality of cam tracks, each cam track engaging a follower associated with a refill holder so that when a selected refill holder is moved into its operative position, the switching element rotates so that it holds the selected refill holder in its writing position.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view, partly in section, of the upper portion of one embodiment of a multicolor writing pen fitted with the cam action and retaining mechanism according to the present invention;

FIG. 2a is a sectional view of another embodiment of a sleeve for the refill-holders of a multicolor writing pen according to the present invention;

FIG. 2b is a side elevational view, partly in section, of a refill holder;

FIG. 2c is a perspective view of a switching element for use in a pen according to the invention;

FIG. 2d is a fragmentary end view of FIG. 2a;

FIG. 22 is an end view of FIG. 2b;

FIGS. 3a and 3b are representations analogous to those in FIGS. 20 and 2b of the sleeve and a refill holder of another embodiment;

FIG. 3c is a fragmentary end view of FIG. 3a; and

FIG. 3d is an end view of FIG. 3b.

DESCRIPTION OF THE PREFERRED EMBODIMENT The multicolor writing pen I illustrated in FIG. 1 comprises a barrel 2 and a pushbutton 4 which is held in the upper end of the barrel 2 in a conventional manner, for instance, by a retaining ring abutting a projecting flange. As shown therein, a selector rod I is suspended from the pushbutton 4, and the rod has an enlarged head I2 which is held in a recess 8 by an inserted ring I4. A spring 6 is supported inside the barrel 2 by a sleeve 42 which will be later described and a cup-shaped element 46. The spring 6 bears upwardly against the pushbutton 4 and keeps it in its normal position.

The refill holders, generally indicated by reference numeral 20, comprise carriers 26 and plungers 22 which are attached thereto and which are each formed at their upper ends with a plunger head 24. The connection between each plunger 22 and the associated carrier 26 is preferably so contrived that the refill carriers 26 can be slightly and preferably resiliently deflected out of their coaxial alignment with the plungers 22. This is necessary to permit the selected refill to be smoothly advanced. Each plunger 22 and its associated carrier 26 are eccentrically interconnected. The plungers 22 are guided inside the barrel 2 in the sleeve 42 located below but within reach of the rod 10. This sleeve 42 contains guideways 43 and 43' (FIGS. 20 and 3a) for the plunger heads 24 and 24, so contrived that the plungers 22 can be pushed vertically downwards by the rod 10 without being rotated.

In the embodiment illustrated in FIG. 2a, the guideways 43 in the sleeve are designed to guidea plunger head 24 of the kind shown in FIG. 2b. This is made possible by the provision of an additional guiding surface 52.

In the embodiment shown in FIGS. 3a3d, the head of the plunger 24' has a projection 54 which engages a cooperating slot 55 in the additional guiding surface 52. In conformity with the circularly arcuate periphery of the plunger head 24' the guideway 43' is likewise arcuately curved in cross section. The cup-shaped element 46 previously mentioned has a polygonal internal contour to permit the rod 10 to locate itself more readily above a selected plunger head. The floor 48 of the cupshaped element 46 contains openings 49 through which the pendant rod 10 can pass. The floor 48 also serves as a bearing for a switching member 30. The bottom end of the sleeve is likewise closed by a floor 44 containing openings 45 below the guideways 43 for the passage therethrough of the selected plunger 22.

In the case of the sleeves shown in FIGS. 2a and 3a, the polygonal internal contour 50 is fonned in the upper end of the sleeve 42 or 42' itself.

Each plunger head 24 which has a larger diameter than the stem 22 of its associated plunger is formed with a socket 33 for a ball 31 which functions as a cam follower. Moreover, each plunger 22 is surrounded by a compression spring 28 of which one end bears against the plunger head 24, whereas the other end stands on the floor 44 of the sleeve 42. The switching element inside the sleeve 42 is an elongated substantially cylindrical body 30 provided with cam slots 36 machined into its surface. The bottom end 34 of the switch cylinder is rotatably mounted in the floor 44 of the sleeve 42. A pin 35 projecting from the bottom end 34 of the cylinder 30 being rotatably received into a central bore 47 in the floor of the sleeve 42. The upper end of the switch cylinder 30 converges to a point 32 which is either rotatably mounted in the underside of the floor 48 of the cup-shaped element '46 or in a central recess in an upper terminal member of a sleeve 42 as shown in FIGS. 2a and 3a, the pin 35 on the switch cylinder which extends into a corresponding hole 47 in the floor 44 of the sleeve being rotatably held by a rivet.

The cam slots 36 which are machined into the peripheral surface of the cylinder 30 are located on the sides facing the cooperating plungers 22 and they comprise an upper curved recess 38 and a bottom retaining recess 40. The balls 31 which are contained in the sockets 33 in the plunger heads 24 engage the respective cam slots. In the case of a four-color pen comprising four refill holders, the switch cylinder will also contain four cam slots.

In operation, the described arrangement functions as follows: by appropriately turning the writing pen while holding it horizontally or slightly inclined, the rod 10 assisted by the polygonal internal contour 50 of the upper part of the sleeve 42 can be made to drop into the desired position above the head 24 of a selected plunger which is to be pushed down. The correct positions for the selection of the writing refills can be simply indicated by corresponding color markings on the outside of the pen. When the button 4 is depressed, the ball 31 contained in the socket 33 of the plunger head 24 slides down the cam slot until it reaches the retaining recess 40. At this point, the thrust of the ball against the sloping edge 39 (see FIG. 20) of the slot will turn the cylinder in the clockwise direction (viewed from above) until the ball reaches the bottom of the recess. When the button 4 is released the plunger head and the ball 31 are urged upwards by the thrust of the Y restoring spring 38., but the ball 31 and hence the plunger head 24 will be retained in writing position by the upper edge 41 of the recess 40. The retraction of the plunger by renewed depression of the button 4 requires the rod to be moved into a position for cooperation with a different plunger head. The ball 31 of the freshly selected head which engages the upper recess 38 of its cooperating cam slot will then be urged against the sloping edge 31 of the slot and impart an anticlockwise rotation to the switch cylinder, thereby releasing the ball 31 of the plunger head which is still in writing position from engagement with the upper edge 41 of the bottom recess and permitting this plunger to be restored to its upper position by the spring 28. The continued depression of the button and hence of the rod 10 will then push the freshly selected plunger head into its operative position, whereas release of the button after partial depression causes both plungers to be restored to inoperative position, i.e. both the plunger that had been in writing position and the plunger that had been partially depressed for releasing the operative plunger.

The embodiments particularly described hereinbefore have a number of advantages over conventional methods of construction used in multicolor pens. The mechanism is simple arid requires only a short operating stroke and minimizes the outside diameter of the pen BARREL. TIIE MINIMAL NUMBER OF PARTS ENsuREs RELIABLE OPERATION AND sIMPLIFIEs THE PRODUCTION AND ASSEMBLY OF SUCH A PEN.

What I claim is:

1. A multicolor writing pen having an outer barrel portion comprising a plurality of refill holders each of which can be moved into an operative or writing position against the action be so moved, and a switching element comprising a rotatable cylinder, the peripheral surface of which is provided with a plurality of cam tracks, each cam track engaging a follower of a plunger means associated with a refill holder so that when a selected refill holder is moved into its operative position, the switching element rotates so that it holds the selected refill holder in its writing position; said cylinder being centrally disposed between all of said plunger means whereby the outside diameter of said outer barrel portion is minimized.

2. The writing pen according to claim 1, wherein said selecting means includes a rod suspended from one end thereof and which under the action of gravity can be arranged to cooperate with a selected one of said refill holders.

3. The writing pen according to claim 2, wherein said rod is suspended from a spring-loaded button.

4. The writing pen according to claim 3, wherein each follower is a captive ball in a socket formed in a plunger secured to an associated refill holder.

5. The writing pen according to claim 4, wherein said plungers are slidable in guideways in a sleeve which supports said switching element and also supports a plurality of compression springs which provide the spring biasing for said refill holders.

6. The writing pen according to claim 5, wherein the bottom end of each plunger is attached eccentrically to its associated refill holder.

7. The writing pen according to claim 6, wherein the upper end of said sleeve carries a terminal member which provides an upper bearing for said switching element and which has a polygonal internal contour, the corners of which align approximately with said plungers.

8. The writing pen according to claim 7, wherein each plunger has a head which has a contour which conforms with the guideway for the plunger.

9. The writing pen according to claim 8, wherein each plunger has a head which has a supplementary guide element which slides in a guiding slot. 

1. A multicolor writing pen having an outer barrel portion comprising a plurality of refill holders each of which can be moved into an operative or writing position against the action of a biasing spring, means for selecting which refill holder is to be so moved, and a switching element comprising a rotatable cylinder, the peripheral surface of which is provided with a plurality of cam tracks, each cam track engaging a follower of a plunger means associated with a refill holder so that when a selected refill holder is moved into its operative position, the switching element rotates so that it holds the selected refill holder in its writing position; said cylinder being centrally disposed between all of said plunger means whereby the outside diameter of said outer barrel portion is minimized.
 2. The writing pen according to claim 1, wherein said selecting means includes a rod suspended from one end thereof and which under the action of gravity can be arranged to cooperate with a selected one of saiD refill holders.
 3. The writing pen according to claim 2, wherein said rod is suspended from a spring-loaded button.
 4. The writing pen according to claim 3, wherein each follower is a captive ball in a socket formed in a plunger secured to an associated refill holder.
 5. The writing pen according to claim 4, wherein said plungers are slidable in guideways in a sleeve which supports said switching element and also supports a plurality of compression springs which provide the spring biasing for said refill holders.
 6. The writing pen according to claim 5, wherein the bottom end of each plunger is attached eccentrically to its associated refill holder.
 7. The writing pen according to claim 6, wherein the upper end of said sleeve carries a terminal member which provides an upper bearing for said switching element and which has a polygonal internal contour, the corners of which align approximately with said plungers.
 8. The writing pen according to claim 7, wherein each plunger has a head which has a contour which conforms with the guideway for the plunger.
 9. The writing pen according to claim 8, wherein each plunger has a head which has a supplementary guide element which slides in a guiding slot. 